MRI Brain Anatomy

Question 1

The 4 major components of the adult brain are

Answer 1

The cerebrum, cerebellum, diencephalon and brainstem.

Question 2

The cerebrum is divided into right and left hemispheres by

Answer 2

the falx cerebri

Question 3

What is a dense bundle of white matter fibers that connects the two hemispheres

Answer 3

The corpus callosum

Question 4

Besides the Corpus Collosum, there are other white matter tracts that transmit electrical impulses throughout the brain and they are:

Answer 4

the internal and external capsules

Question 5

Projection fibers relay information from the cerebral cortex through the brainstem downward into the cord. These fibers cross at the _____. Therefore, if a patient has a stroke or injury on the left side of the brain, the right side of the body manifests symptoms.

Answer 5

medulla

Question 6

Where is the Cerebral cortex located?

Answer 6

The outer layer of the brain is the cerebral cortex.

Question 7

A cluster of subcortical gray matter in the brain is the

Answer 7

basal ganglia

Question 8

What are the main portions of the basal ganglia?

Answer 8

The main portions of the basal ganglia are the caudate nucleus, lentiform nucleus and the claustrum.

Question 9

Does the basal ganglia enhance on postcontrast images?

Answer 9

The basal ganglia does not enhance on postcontrast images

Question 10

The diencephalon is a gray or white matter area that lies above the brainstem.

Answer 10

The diencephalon is a gray matter area that lies above the brainstem.

Question 11

The diencephalon is composed of what four areas?

Answer 11

The diencephalon is composed of the thalamus, subthalamus, epithalamus and hypothalamus.

Question 12

The epithalamus is the ____ gland and its stalk, the infundibulum.

Answer 12

The epithalamus is the pineal gland and its stalk, the infundibulum.

Question 13

There are 3 parts of the brainstem.

Answer 13

The most superior portion of the brainstem is the midbrain. The anterior portion of the midbrain is composed of the cerebral peduncles, and the posterior section of the colliculi (corpora quadrigemina). The superior colliculus relays visual information and the inferior colliculus is an auditory pathway. The pons, which means “little belly” in Latin, is an area that bulges anteriorly and sends information between the midbrain and the medulla.

Question 14

The medulla oblongata is located where in comparison to the pons

Answer 14

Beneath the pons is the medulla oblongata.

Question 15

The cerebellum, often called the “_____ _____”

Answer 15

little brain

There are 2 cerebellar lobes separated by the folds of the falx cerebelli and connected in specific areas by the vermis.

Question 16

The delicate brain is protected by 3 meningeal layers.

What are the 3 layers?

Answer 16

The strong, durable outer layer has 2 parts and is known as the dura mater. The meningeal arteries and the dural sinuses lie between the 2 layers of dura mater.

The arachnoid membrane is a delicate, spider-like layer beneath the dura mater. The area under the arachnoid is called the subarachnoid space. CSF circulates around the brain and spinal cord in the subarachnoid space, providing buoyancy and protection for the delicate structures.

The layer nearest the cerebral cortex is the pia mater. It is a highly vascular structure that adheres to the folds of the brain.

Question 17

What system transports CSF throughout the central nervous system.

Answer 17

The ventricular system transports CSF throughout the central nervous system.

Question 18

The ventricular system transports CSF throughout the central nervous system. The system includes:

Answer 18

The ventricular system transports CSF throughout the central nervous system. The system includes 2 lateral ventricles, a third ventricle and a fourth ventricle.

Question 19

The _____ _____ (aqueduct of Sylvius) connects the third ventricle to the fourth ventricle.

Answer 19

The cerebral aqueduct (aqueduct of Sylvius) connects the third ventricle to the fourth ventricle.

Question 20

CSF moves around the spinal cord and back into the dural sinuses, where it is absorbed in the _____ _____ _____.

Answer 20

CSF moves around the spinal cord and back into the dural sinuses, where it is absorbed in the superior sagittal sinus

Question 21

A network of blood vessels called the choroid plexus is located within the ventricles. The choroid plexus is responsible for daily production of _____.

Answer 21

A network of blood vessels called the choroid plexus is located within the ventricles. The choroid plexus is responsible for daily production of CSF.

Question 22

The myelin of an infant is not well developed until the age of _____

Answer 22

The myelin of an infant is not well developed until the age of 2 years

Question 23

Brain tissue in an infant 2 years or younger appears isointense, meaning there is not much contrast between the gray and white matter.

If a radiologist wants to better define this area, an _____ _____ _____ is helpful.

Answer 23

Brain tissue in an infant 2 years or younger appears isointense, meaning there is not much contrast between the gray and white matter.

If a radiologist wants to better define this area, an inversion recovery sequence is helpful.

Question 24

_____ occurs when an anatomical structure fails to develop in utero

Answer 24

Agenesis occurs when an anatomical structure fails to develop in utero

Question 25

_____ is when a structure develops abnormally.

Answer 25

Dysgenesis is when a structure develops abnormally

Question 26

_____-_____ _____ is a congenital brain malformation in which the fourth ventricle is enlarged, causing extreme accumulation of CSF in the posterior fossa area of the brain.

Answer 26

Dandy-Walker syndrome is a congenital brain malformation in which the fourth ventricle is enlarged, causing extreme accumulation of CSF in the posterior fossa area of the brain.

Question 27

When the posterior part of the skull is narrower than normal, this is called a Chiari malformation.

Answer 27

A Chiari malformation occurs when the posterior part of the skull is narrower than normal.

Question 28

There are four types of Chiari Form malformations. Of the four, which is the most series and which is the most common?

Answer 28

Even though type III is uncommon, it is the most serious type of Chiari malformation.

Question 29

Inflammation of the brain is referred to as _____

Answer 29

Inflammation of the brain is referred to as encephalitis.

Question 30

Inflammation generally appears _____ on T2-weighted images; radiologists check the brain for symmetry because mass effect also may be present.

Answer 30

Inflammation generally appears hyperintense on T2-weighted images; radiologists check the brain for symmetry because mass effect also may be present.

Question 31

Meningitis indicates inflammation of the _____.

Answer 31

Meningitis indicates inflammation of the meninges.

Question 32

_____ _____, is a common white matter disease that affects the myelin in the brain.

Answer 32

Multiple sclerosis, or MS, is a common white matter disease that affects the myelin in the brain.

Question 33

Multiple Sclerosis Lesions are _____ on T1-weighted images and _____ on T2-weighted images.

Answer 33

Lesions are isointense on T1-weighted images and hyperintense on T2-weighted images.

Question 34

The term “neoplasia” means _____ _____.

Answer 34

The term “neoplasia” means new growth

Question 35

Brain tumors are classified as _____ or _____.

Answer 35

Brain tumors are classified as intracranial or extracranial.

Question 36

Where are Gliomas found.

Answer 36

Gliomas are cancerous tumors found only within the brain or spinal cord.

They are graded 1 to 4; the highest grade, glioblastoma multiforme, is the most aggressive. A glioma that transverses both hemispheres of the brain is a butterfly glioma.

Question 37

Meningiomas are benign tumors that grow from or on the meninges; therefore, their location is on top of the brain tissue. Since they do not grow within brain tissue, they are classified as _____ tumors.

Answer 37

Meningiomas are benign tumors that grow from or on the meninges; therefore, their location is on top of the brain tissue. Since they do not grow within brain tissue, they are classified as extracranial tumors.

Question 38

How do meningiomas appear on a precontrast T1 and post contrast T2 weighted image

Answer 38

Meningiomas are isointense on precontrast T1 images, and hyperintense on T1-weighted post contrast images.

Question 39

Acoustic neuromas are benign, slow-growing tumors located on the seventh and eighth cranial nerves. They also are considered intracranial or extracranial tumors because of their location in the petrous ridge.

Answer 39

Acoustic neuromas are benign, slow-growing tumors located on the seventh and eighth cranial nerves. They also are considered extracranial tumors because of their location in the petrous ridge.

Question 40

An _____ occurs when an arterial wall weakens and fills with an abnormal amount of blood.

Answer 40

An aneurysm occurs when an arterial wall weakens and fills with an abnormal amount of blood.

Question 41

The 2 major types of strokes are ischemic and hemorrhagic. Nearly 80% to 90% of strokes are considered _____

Answer 41

A stroke occurs when there is a sudden disruption of blood flow to the brain, resulting in damage to brain tissue. The 2 major types of strokes are ischemic and hemorrhagic. Nearly 80% to 90% of strokes are considered ischemic and are caused when stenosis, a thrombus or an embolism blocks the arteries.

Question 42

A smaller number of strokes are classified as _____, the consequence of blood vessel leakage or rupture.

Answer 42

A smaller number of strokes are classified as hemorrhagic, the consequence of blood vessel leakage or rupture.